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Merge branch 'refactor/ldgen_library_deps' into 'master'
refactor(cmake): collect libraries from ELF, don't depend on idf_build_target Closes IDF-10772 See merge request espressif/esp-idf!34520
2 parents 762cf05 + 431ee5c commit d38c05c

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3 files changed

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‎tools/cmake/build.cmake‎

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@@ -712,6 +712,9 @@ endmacro()
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# files used for linking, targets which should execute before creating the specified executable,
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# generating additional binary files, generating files related to flashing, etc.)
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function(idf_build_executable elf)
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# Create a target for linker script generation for this executable
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__ldgen_create_target(${elf})
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# Set additional link flags for the executable
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idf_build_get_property(link_options LINK_OPTIONS)
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set_property(TARGET ${elf} APPEND PROPERTY LINK_OPTIONS "${link_options}")

‎tools/cmake/component.cmake‎

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@@ -494,7 +494,6 @@ function(idf_component_register)
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__component_add_include_dirs(${component_lib} "${__PRIV_INCLUDE_DIRS}" PRIVATE)
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__component_add_include_dirs(${component_lib} "${config_dir}" PUBLIC)
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set_target_properties(${component_lib} PROPERTIES OUTPUT_NAME ${COMPONENT_NAME} LINKER_LANGUAGE C)
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__ldgen_add_component(${component_lib})
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else()
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add_library(${component_lib} INTERFACE)
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__component_set_property(${component_target} COMPONENT_TYPE CONFIG_ONLY)

‎tools/cmake/ldgen.cmake‎

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@@ -15,25 +15,134 @@ function(__ldgen_add_fragment_files fragment_files)
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idf_build_set_property(__LDGEN_FRAGMENT_FILES "${_fragment_files}" APPEND)
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endfunction()
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# __ldgen_add_component
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#
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# Generate sections info for specified target to be used in linker script generation
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function(__ldgen_add_component component_lib)
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idf_build_set_property(__LDGEN_LIBRARIES "$<TARGET_FILE:${component_lib}>" APPEND)
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idf_build_set_property(__LDGEN_DEPENDS ${component_lib} APPEND)
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endfunction()
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# __ldgen_process_template
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#
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# Passes a linker script template to the linker script generation tool for
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# processing
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# processing. This internal function is called from the public "target_linker_script" function.
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# It simply records the template and output file names. The actual linker script generation
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# target is created later by the __ldgen_create_target function.
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#
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function(__ldgen_process_template template output)
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idf_build_set_property(__LDGEN_TEMPLATES "${template}" APPEND)
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idf_build_set_property(__LDGEN_OUTPUTS "${output}" APPEND)
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endfunction()
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# __ldgen_get_lib_deps_of_target
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#
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# Helper function to get the list of libraries that a target depends on,
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# recursively, and append it to the out_list. The 'target' argument is
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# typically an executable.
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#
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function(__ldgen_get_lib_deps_of_target target out_list_var)
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set(out_list ${${out_list_var}})
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if(target IN_LIST out_list)
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# This target is already in the list, meaning that it has been
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# processed already. Bail out.
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return()
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endif()
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# The target is not in the list yet. Add it, and then add all its dependencies.
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list(APPEND out_list ${target})
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set(${out_list_var} ${out_list} PARENT_SCOPE)
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get_target_property(target_deps ${target} LINK_LIBRARIES)
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if(NOT target_deps)
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# This target has no dependencies, nothing to do.
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return()
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endif()
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foreach(dep ${target_deps})
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if(dep IN_LIST out_list)
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# This dependency has already been processed, skip it.
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continue()
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endif()
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if(NOT TARGET ${dep})
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# LINK_LIBRARIES may contain various non-library-related linker flags
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# (-u, -L, -l, etc.), skip them.
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if(dep MATCHES "^-" OR dep MATCHES "^\:\:")
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continue()
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endif()
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# If the dependency is not a target, it may be a library. Add it to the list.
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list(APPEND out_list ${dep})
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else()
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# Recursively add the dependencies of this target.
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__ldgen_get_lib_deps_of_target(${dep} out_list)
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endif()
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endforeach()
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set(${out_list_var} ${out_list} PARENT_SCOPE)
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endfunction()
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# __ldgen_create_target
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#
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# Internal function which creates a custom target for the linker script generation tool.
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# This function is called from the public idf_build_executable function.
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#
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function(__ldgen_create_target exe_target)
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idf_build_get_property(idf_target IDF_TARGET)
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idf_build_get_property(idf_path IDF_PATH)
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idf_build_get_property(templates __LDGEN_TEMPLATES)
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idf_build_get_property(outputs __LDGEN_OUTPUTS)
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if(NOT templates)
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# No templates were passed to ldgen, nothing to do.
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return()
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endif()
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list(LENGTH templates num_templates)
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if(NOT num_templates EQUAL 1)
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# This limitation can be removed, if necessary, by looping over the list of templates
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# and creating a target for each one of them.
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# However, this is not needed in IDF for now, hence the simpler implementation.
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message(FATAL_ERROR "Only one template file can be passed to __ldgen_process, "
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"got ${num_templates}: ${templates}")
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endif()
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list(GET templates 0 template)
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list(GET outputs 0 output)
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# Collect all the libraries that the executable depends on, recursively.
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# This is needed to pass the list of libraries to the linker script generator tool.
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set(ldgen_libraries)
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__ldgen_get_lib_deps_of_target(${exe_target} ldgen_libraries)
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list(REMOVE_ITEM ldgen_libraries ${exe_target})
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set(ldgen_deps)
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foreach(lib ${ldgen_libraries})
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if(TARGET ${lib})
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get_target_property(lib_type ${lib} TYPE)
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if(lib_type STREQUAL "INTERFACE_LIBRARY")
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continue()
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endif()
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list(APPEND ldgen_libraries_expr "$<TARGET_FILE:${lib}>")
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list(APPEND ldgen_deps ${lib})
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else()
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# Here we have two cases:
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#
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# 1. ${lib} is actually a target, but the target is outside the current scope.
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# This is the case for imported library targets (such as those added by
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# add_prebuilt_library), since by default imported targets are not
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# visible outside the directory where they are defined, unless they are
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# marked as GLOBAL.
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# This case covers many (but not all) of IDF's prebuilt libraries.
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#
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# 2. ${lib} is the name of a library, which the linker can find in its built-in
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# or specified search paths.
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# This is the case for toolchain libraries (m, c, gcc, stdc++) as well
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# as for some prebuilt libraries which have been added using `-lname -Lpath`
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# style flags.
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#
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# If we can successfully find the absolute path of each such library, this
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# will allow us to pass them to ldgen, enabling us to place functions from
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# prebuilt libraries to specific sections in the linker script (IDF-12049)
140+
endif()
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endforeach()
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list(JOIN ldgen_libraries_expr "\n" ldgen_libraries_str)
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34144
idf_build_get_property(build_dir BUILD_DIR)
35-
idf_build_get_property(ldgen_libraries __LDGEN_LIBRARIES GENERATOR_EXPRESSION)
36-
file(GENERATE OUTPUT ${build_dir}/ldgen_libraries.in CONTENT $<JOIN:${ldgen_libraries},\n>)
145+
file(WRITE ${build_dir}/ldgen_libraries.in "${ldgen_libraries_str}")
37146
file(GENERATE OUTPUT ${build_dir}/ldgen_libraries INPUT ${build_dir}/ldgen_libraries.in)
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39148
set_property(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
@@ -42,7 +151,7 @@ function(__ldgen_process_template template output)
42151
"${build_dir}/ldgen_libraries")
43152

44153
idf_build_get_property(ldgen_fragment_files __LDGEN_FRAGMENT_FILES GENERATOR_EXPRESSION)
45-
idf_build_get_property(ldgen_depends __LDGEN_DEPENDS GENERATOR_EXPRESSION)
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46155
# Create command to invoke the linker script generator tool.
47156
idf_build_get_property(sdkconfig SDKCONFIG)
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idf_build_get_property(root_kconfig __ROOT_KCONFIG)
@@ -69,12 +178,15 @@ function(__ldgen_process_template template output)
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--libraries-file "${build_dir}/ldgen_libraries"
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--objdump "${CMAKE_OBJDUMP}"
71180
${ldgen_check}
72-
DEPENDS ${template} ${ldgen_fragment_files} ${ldgen_depends} ${SDKCONFIG}
181+
DEPENDS ${template} ${ldgen_fragment_files} ${ldgen_deps} ${SDKCONFIG}
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VERBATIM
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)
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185+
# The executable depends on the output of the ldgen command.
76186
get_filename_component(_name ${output} NAME)
77187
add_custom_target(__ldgen_output_${_name} DEPENDS ${output})
78-
add_dependencies(__idf_build_target __ldgen_output_${_name})
188+
add_dependencies(${exe_target} __ldgen_output_${_name})
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# Add the output of the ldgen command to the list of link dependencies.
79191
idf_build_set_property(__LINK_DEPENDS ${output} APPEND)
80192
endfunction()

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